From: David Howells <dhowells@xxxxxxxxxx>
[ Upstream commit ca57f02295f188d6c65ec02202402979880fa6d8 ]
The fileserver probing code attempts to work out the best fileserver to
use for a volume by retrieving the RTT calculated by AF_RXRPC for the
probe call sent to each server and comparing them. Sometimes, however,
no RTT estimate is available and rxrpc_kernel_get_srtt() returns false,
leading good fileservers to be given an RTT of UINT_MAX and thus causing
the rotation algorithm to ignore them.
Fix afs_select_fileserver() to ignore rxrpc_kernel_get_srtt()'s return
value and just take the estimated RTT it provides - which will be capped
at 1 second.
Fixes: 1d4adfaf6574 ("rxrpc: Make rxrpc_kernel_get_srtt() indicate validity")
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Reviewed-by: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
Tested-by: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
cc: linux-afs@xxxxxxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/166965503999.3392585.13954054113218099395.stgit@xxxxxxxxxxxxxxxxxxxxxx/
Signed-off-by: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/afs/fs_probe.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/afs/fs_probe.c b/fs/afs/fs_probe.c
index e7e98ad63a91..04d42e49fc59 100644
--- a/fs/afs/fs_probe.c
+++ b/fs/afs/fs_probe.c
@@ -161,8 +161,8 @@ void afs_fileserver_probe_result(struct afs_call *call)
}
}
- if (rxrpc_kernel_get_srtt(call->net->socket, call->rxcall, &rtt_us) &&
- rtt_us < server->probe.rtt) {
+ rxrpc_kernel_get_srtt(call->net->socket, call->rxcall, &rtt_us);
+ if (rtt_us < server->probe.rtt) {
server->probe.rtt = rtt_us;
server->rtt = rtt_us;
alist->preferred = index;
--
2.35.1
